Looking on the bright side may do more than just help you get through tough times—it might actually help you live longer. In a new Harvard University study, women who had an optimistic outlook were less likely to die from several causes, including top killers like heart disease, cancer, and infection. The study isn’t the first to make a connection between optimism and health benefits; other research has linked the positive-thinking personality trait to a lower risk of dying from cardiovascular problems, for example.